Film maker spends several hours at the bottom of the Mariana Trench

Film director James Cameron has completed his journey to the earth's deepest point.

The director of Titanic and Avatar used a specially designed submarine to dive nearly 11 kilometres to the botttom of the Mariana Trench in the western Pacific.

Mr Cameron spent just over three hours under water after reaching a depth of 10,898 metres before he began his return to the surface.

He had planned to spend up to six hours on the sea floor.

Mr Cameron's return aboard his sub called Deepsea Challenger was a faster-than-expected 70-minute ascent, according to National Geographic, which is part of the expedition team.

National Geographic's Terry Garcia says it's really the first time that human eyes have had an opportunity to gaze upon what is a very alien landscape.

In 1960 Swiss engineer Jacques Piccard and Don Walsh, a US Navy captain, spent about 20 minutes at the bottom of the Trench but they couldn't see much after their submarine kicked up sand from the sea floor.